I think what you mean is "strainer beam." It's a beam used in construction used strengthen or support.


www.rchme.gov.uk/thesaurus/components/s/133694.htm describes it as:
A transverse timber in aisled construction, joining aisle posts below tiebeam level, to allow rearing of pairs of posts.

American Heritage® Dictionary lists strainer as:
An apparatus for tightening, stretching, or strengthening.

Rasuk is defined by Dewan Bahasa and Pustaka as:
Komponen struktur yang biasanya berkedudukan mengufuk dan berfungsi untuk memindahkan beban dinding dan lantai kepada tiang.

example of usage (rasuk melintang):
www.hbp.usm.my/norizal/lectures/S-idealisation.htm